Merge "Revert "Icon: make Icon's Bitmaps immutable"" into tm-dev am: 4e8c47ef am: cd3ac5bf am: b68c1920 am: a1d430ea

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17919920



Change-Id: Ie79bb40eebbec5bea5acbd272767c71d06f89f3a
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>